Can someone with dementia create a valid will?

With an ever-growing and aging population, along with prolonged lifespans, an increasing number of wills are being disputed due to doubts over testamentary capacity. 

Dementia is a condition predominantly linked with the aging population, and the number of people diagnosed with the disease is set to rise to over 1,000,000 by 2025. Those familiar with it understand its impact on both the individual with the diagnosis and their loved ones.

Contrary to popular belief, receiving a dementia diagnosis does not automatically mean a person cannot make a will to say who their money and possessions should go to after they die. Instead, it depends on whether a person is able to understand and make decisions specifically about the will.

In this article, Anjali Narshi, contentious probate specialist in Lodders’ Dispute Resolution team, highlights how you can establish whether someone has what is known as “testamentary capacity.”

 Testamentary capacity: a definition

 Testamentary capacity refers to the capacity, or understanding, required to make a valid will. If someone is concerned that the testator (the person making the will) did not have capacity when they created a will, they may be able to challenge its legality.

For a claim to be successful, it must be shown that the testator lacked testamentary capacity. This is a very specific requirement.

Claims under this ground are usually bought when the testator had a medical diagnosis of, for example, dementia, depression, anxiety, psychosis, confusion, and personality disorders, to name just a few. These can all impact a testator’s ability to make a will to varying degrees, though each case is, of course, fact specific.

Fluctuating capacity

A characteristic of most types of dementia is good days and bad days, and many factors can influence how cognitively alert a person is and how able they are to participate in daily life at any given time. For instance, it is not unusual for a sufferer to be better in the morning than the afternoon, or for their capacity to be affected by certain medications.

This fluctuation in capacity can make it difficult for solicitors when assessing whether a person had capacity when they executed their will and can therefore lead to disputes.

Case example: Thomas

As an example, let us imagine that a client, who we’ll name Thomas, has sought legal assistance regarding a family dispute arising from his mother’s recent passing and the discovery of a new will that excluded his brother, who we’ll call John, from receiving any inheritance.

John wants to dispute the new will, not only because it did not mention him, but also because it had been made just a few weeks before their mother died. He claims the will is invalid because his mother had been diagnosed with dementia, and therefore lacked testamentary capacity to make a will.

When speaking to his solicitor, Thomas disclosed the family’s strained dynamics, explaining that John had been estranged for nearly two decades. Having made many unsuccessful attempts at reconciliation of the years, their mother, battling terminal illness and the onset of dementia, decided to revise her will and leave everything to Thomas.

Thomas affirmed his mother’s clarity and intent in making the changes, facilitated by a solicitor who noted her cognitive soundness despite her declining health. This was also supported by her medical records at the time of making the will.

Key factors to determining capacity

As stated above, a person is considered to have testamentary capacity if they are able to understand and make decisions specifically relating to their will.

In the case example above, Thomas’s solicitor would need to conduct a detailed review of Thomas’s mother’s medical records, her solicitor’s notes, and consult with those who spent most time with his mother in the weeks and months before her death. Central to the inquiry would be determining her mental capacity to execute a valid will and understand its implications and her assets.

A person has testamentary capacity to make a will if they:

  • Understand that they are making a will and appreciate its effects;
  • Have some understanding of the extent of their property;
  • Comprehend the individuals for whom they would usually be expected to provide; and
  • Are not affected by any ‘disorder of mind or insane delusion’.

The case example highlights the complexity of such cases, where decision-making capacity varies, and thorough investigations are necessary. It also highlights how critical it is to ensure that a will is regularly reviewed and updated where necessary – after all, family life and relationships change and it’s important that a will is updated to reflect this.

Lodders is a premier law firm in Stratford upon Avon, Cheltenham, Henley in Arden, and Birmingham. Founded more 240 years ago, the firm offers expert legal advice across a range of legal services including private client, commercial law, real estate, and family law.

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